Spiral binding



' zmms Jan. 14, 1941.

W. GRUMBACHER SPIRAL BINDING Original Filed Dec. 13, 1935 IN VENTOR.

Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE SPIRAL BINDING Qriginal application December 13, 1935, Serial No. 54,210. Divided and this application June 29, 1938, Serial No. 216,439

8 Claims.

This invention relates generally to the binding of sheaves or stacks of paper or the like and more particularly to such binding by means of a spiral binding element.

The present application constitutes a division of my copending application Serial No. 54,210, filed December 13, 1935.

The general object of my invention is a novel arrangement in a binder for a stack of sheets, whereby the cover members can be swung to and from a position of superposed parallelism.

I have illustrated and will herein describe my invention as embodied in that type of binding which has. come to be known as a spiral binding and which consists essentially of a spiral or helical binding wire or element passing through spaced perforations along one edge of the stack, the spacing between the perforations corresponding to the pitch of the spiral binder. The stack is free to swing about the binding element which is made up of a series of coaxially disposed loops.

One embodiment of my invention is shown in the accompanying drawing, in which:

Figure 1 is a fragmentary plan view of a bound sheaf of improved characteristics embodying the features of my present invention;

Figure 2 is an enlarged sectional view with portions broken away on the line 2-2 of Figure 1 looking in the direction of the arrows; and

Figure 3 is an illustration of a constructional detail.

On viewing Figures 1 and 2 of the drawing it will be observed that I have therein shown a sheaf or stack of bound sheets 16 and a backing therefor comprising two lateral portions and 62, which are connected by an intermediate portion comprising a flange or section 64 upstanding from the portion 6i], and a flange or section 66 upstanding from the portion 62, and these flanges are provided respectively with rows of perforations [it and ill, which are in registration with each other so that the binding element 12 may be received therethrough and also through the perforations l4,'shown as provided in a stack 16. The portions El], 62, 64 and 66 may be parts of an integral piece of flexible material, and in that case the portions 62 may be brought into the position 62' and by further manipulation into the position overlying the stack 15. It will be noted that the sections 64 and 66 are hinged to each other along their outer edges so that the cover members can swing freely about the hinge from the full line position of Figure 2 to a position of superposed parallelism.

(Cl. ESL-29) The spiral binding construction just described requires for its smooth operation that at least portions of the perforations 68 and 1E! are in registration with the turns of the spiral and since the latter are pitched progressively it is obvious that although the perforations 68 and Ill are in registration with the portions of the spiral 12 passing therethrough when the cover is in the full line position of Figure 2, they may not be in registration with the spiral portions when the dot and dash line position and other positions beyond this are assumed by the cover section 62.

Figure 3 is intended to show that a pair of directly opposed openings e and f on opposite sides of a central line of flexure, indicated by the dotted lines, may, if their diameter is made sufliciently great, permit the angling of the cover about the central line of fiexure without binding even where the binder is spiral in character. This will be obvious from the figure, from which it appears that if the left hand cover section is angled the spiral portion g will move downward relatively thereto and when the left hand section of the cover is superposed over the right hand section of the cover the spiral will touch the lower edge of the opening 1, assuming that the spiral has not been shifted laterally in relation to the cover.

On viewing Figure 2 it will be observed that the openings 68 and It are shown so spaced in relation to each other that both sections 62 and M of the cover are always constrained to remain on the same side of the spiral axis. This is due to the fact that the spacing between the outer edges of the openings 68 and Ill is less than the outer diameter of the spiral 12. From this it follows that if the cover section M and the spiral 12, in the showing of Figure 2, are held stationary, while the cover section 62, and with it section 66, are moved clockwise, about the central crease as an axis, a point will be reached long before the section 66 has been angled through at which further move-- ment is prevented by the contact of the spiral '52 with the walls of the openings 70. In other words the section 66 must always remain on the same side of the spiral axis as the section 64.

The same will be found to be true if the spiral is released so that it is free to move relatively to the cover section 64. In that case, while sections 66 and 64 may possibly turn relatively through an angle greater than 180, nevertheless, no matter what angle they assume, it will be found that they must always lie on the same side of the spiral axis.

When therefore the sections 62 and 60 are arranged so as to overlie the opposite sides of the stack, and the sections 66 and 64 are disposed symmetrically in relation to the stack it will be found that the inner end of the stack and sections 66 and 64 are disposed on opposite sides of the spiral axis.

While I have herein disclosed several illustrative embodiments of my invention it will be understood that the same may be embodied in many other forms without departing from the spirit thereof, as will be obvious to those skilled in the art, and that the disclosure herein is by way of illustration merely and is not to be interpreted in a limiting sense, and that I do not limit myself other than as called for by the prior art.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent, is:

1. In combination, a stack of sheets having a row of equally spaced perforations adjacent one edge thereof, a cover for said stack of sheets, a flexible fold in said cover at an intermediate portion dividing it into sections and serving as a hinge for said sections, and said sections not being connected so that they are free to angle relatively to each other, a row of perforations pitched to correspond withthe perforations in the stack running parallel to and in spaced adjacency to said fold in the cover on each side of said fold, and a spiral binding element passing through said perforations in the stack and in the cover, and said perforations of each row being so positioned and dimensioned relatively to the perforations of the other row that each perforation of one row has a substantial portion thereof registering with a substantial portion of a perforation of the other row which is opposed thereto, whereby the cover sections may be angled about said fold through an angle of the order of without binding of the spiral in the perforations.

2. In combination, a stack of sheets having a row of equally spaced perforations adjacent one edge thereof, a cover for said stack of sheets, a pair of parallel rows of perforations pitched to correspond with the perforations in the stack running across said cover at an intermediate point, a fold in said cover intermediate said rows of perforations, and a spiral binding element passing through said perforations in the stack and in the cover, the material of said cover at said fold being flexible so as to permit relative angling of the sections of said cover on opposite sides of said fold, said sections being unconnected to each other except at said fold, and the perforations of said two rows being paired in opposed relation and having portions thereof in registration whereby the cover portions on opposite sides of said fold may angle relatively to each other through a substantial distance without binding, and the outer diameter of said spiral being greater than the distance between the outermost portions of the two rows of perforations.

3. A book construction comprising a stack of sheets, a cover for said stack having a single fold extending thereacross and dividing it into two portions, spaced openings disposed on each side of said fold, a binding element comprising a plurality of coaxially disposed loops spaced soas to register with said openings and having its loops passing through said openings, and the sheets of the stack having loop engaging portions thereon whereby they are slidably hung therefrom, said fold being disposed so as to lie within said loops and the cover portions inside the loop and on both sides of said fold being unconnected and the openings on opposite sides of said row having substantial portions of opposed openings in registration with each other, whereby said cover portions inside the loop and on opposite sides of said fold are free to angle relatively to each other.

4. In combination, a stack of sheets having a row of equally spaced perforations adjacent one edge thereof, a cover for said stack of sheets, a pair of parallel rows of perforations pitched to correspond with .the perforations in the stack running across said cover at an intermediate point, a single crease in said cover intermediate said rows of perforations, and a spiral binding element passing through said perforations in the stack and in the cover, the material of said cover at said crease being flexible so as to permit relative angling of the sections of said cover on opposite sides of said crease, said sections being unconnected to each other, and the perforations of said two rows being paired in opposed relation and the diameter and positioning of said perforations being portions of said opposed perforations register so that the spiral will pass therethrough without binding in all relative positions of the cover portions on opposite sides of said crease throughout a range of relatively angled positions thereof exceeding a right angle, and the outer diameter of said spiral being greater than the distance between the outermost portions of the two rows of perforations.

5. In combination, a stack of sheets having a row of equally spaced perforations adjacent one edge thereof, a cover for said stack of sheets, a pair of parallel rows of perforations pitched to correspond with the perforations in the stack running across said cover at an intermediate point, a portion of said cover intermediate said rows of perforations being flexible, and a spiral binding element passing through said perforations in the stack and in the cover, and the outer diameter of the spiral being greater than the transverse distance between the outermost portions of the two rows of perforations, and the perforations of said rows being so positioned and dimensioned as to permit of the relative angling of the sections of said cover containing the respective rows of perforations about an intermediate line without binding of the spiral in the perforations through an angle greater than a right angle, and a bend in each of said cover portions positioned outside of the spiral loops and in relative adjacency thereto.

6. In combination, a stack of sheets having a row of equally spaced perforations adjacent one edge thereof, a cover for said stack of sheets, a flexible fold in said cover at an intermediate portion dividing it into sections and serving as a hinge for said sections, and said sections not being connected so that they are free to angle relatively to each other, a row of perforations pitched to correspond with the perforations in the stack running parallel to and in spaced adjacency to said fold in the cover on each side of said fold, and a spiral binding element passing through said perforations in the stack and in the cover, and said perforations of each row being so positioned and dimensioned relatively to the perforations of the other row that each perforation of one row has a substantial portion thereof registering with a substantial portion of a perforation of the other row which is opposed thereto, whereby the cover sections may be angled about said fold through an angle of the order of 180 without binding of the spiral in the perforations, and the outer diameter of said spiral being greater than the distance between the outermost portions of the two rows of perforations, whereby both rows of perforations are constrained to remain on the same side of the spiral axis.

7. In a binder for a stack of sheets, a pair of cover members, each having a flange, the flanges being hinged to each other along their free edges whereby to permit said cover members to swing freely into superposed parallel relation, the flanges being each provided with apertures in registration with the apertures of the other flange and having means for securing a stack of sheets in position comprising coaxially disposed loops engaged respectively through registering apertures in the aforementioned two flanges.

8. In a binder for a stack of sheets, a pair of cover members, each having a flange, the flanges being hinged to each other along their free edges whereby to permit said cover members to swing freely into superposed parallel relation, the flanges being each provided with apertures in registration with the apertures of the other flange and having means for securing a stack of sheets in position comprising coaxially disposed loops engaged respectively through registering apertures in the aforementioned two flanges, the registering apertures being so spaced. and sized that their outermost portions will be spaced apart less than the outermost diameter of the loop received therethrough when the two flanges are moved to their fully extended position into a common plane.

WALTER GRUMBACHER. 

